Abstract.The primary goal of the Genetics and Neuroendocrinology of Short Stature International
Study (GeNeSIS) was to assess the safety and effectiveness of Humatrope®, a GH
preparation, in the treatment of pediatric patients with short stature. We report our
findings in the GH-treated Japanese pediatric population focusing on the incidence of type
2 diabetes (T2D) and occurrence of neoplasms. A total of 2,345 Japanese patients were
assessed for safety. During a mean observation period of 3.2 yr, T2D occurred in 3
patients (0.13%) and slowly progressive insulin-dependent diabetes mellitus (SPIDDM)
related to underlying mitochondrial encephalomyopathy, lactic acidosis, and stroke-like
episodes (MELAS) in 1 patient (0.04%). Neoplasms were reported in 13 patients (0.56%),
including 1 patient with brain tumor (germinoma) and 5 with craniopharyngiomas (4
recurrences); the remainder were benign, typically dermatological, neoplasms. The
incidence of diabetes mellitus determined in the study did not differ from previous
reports in GH-treated pediatric patients, and there was no apparent increase in the risk
of new neoplastic lesions or malignant tumors.